Radiative three-loop

Corrections of order Y ZaY are generated by three-loop radiative insertions in the skeleton diagram in Fig. 3.8. All such corrections connected with the diagrams containing at least one one-loop or two-loop polarization insertion were obtained in [58]... 

Calculation of corrections generated by the gauge invariant set of diagrams with insertions of three radiative photons in the electron line in the skeleton diagrams in Fig. 9.2 is more complicated. Only insertions of the three-loop one-particle reducible diagrams with radiative photons in the electron line in Fig. 9.10 were considered thus far. Contribution of these diagrams in the Yennie gauge is equal to [29]... 

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